ffmpeg / libavutil / mathematics.h @ 80a289b9
History  View  Annotate  Download (1.68 KB)
1 
/*


2 
* copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>

3 
*

4 
* This file is part of FFmpeg.

5 
*

6 
* FFmpeg is free software; you can redistribute it and/or

7 
* modify it under the terms of the GNU Lesser General Public

8 
* License as published by the Free Software Foundation; either

9 
* version 2.1 of the License, or (at your option) any later version.

10 
*

11 
* FFmpeg is distributed in the hope that it will be useful,

12 
* but WITHOUT ANY WARRANTY; without even the implied warranty of

13 
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

14 
* Lesser General Public License for more details.

15 
*

16 
* You should have received a copy of the GNU Lesser General Public

17 
* License along with FFmpeg; if not, write to the Free Software

18 
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

19 
*/

20  
21 
#ifndef MATHEMATICS_H

22 
#define MATHEMATICS_H

23  
24 
#include "rational.h" 
25  
26 
enum AVRounding {

27 
AV_ROUND_ZERO = 0, ///< round toward zero 
28 
AV_ROUND_INF = 1, ///< round away from zero 
29 
AV_ROUND_DOWN = 2, ///< round toward infinity 
30 
AV_ROUND_UP = 3, ///< round toward +infinity 
31 
AV_ROUND_NEAR_INF = 5, ///< round to nearest and halfway cases away from zero 
32 
}; 
33  
34 
/**

35 
* rescale a 64bit integer with rounding to nearest.

36 
* a simple a*b/c isn't possible as it can overflow

37 
*/

38 
int64_t av_rescale(int64_t a, int64_t b, int64_t c); 
39  
40 
/**

41 
* rescale a 64bit integer with specified rounding.

42 
* a simple a*b/c isn't possible as it can overflow

43 
*/

44 
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding);

45  
46 
/**

47 
* rescale a 64bit integer by 2 rational numbers.

48 
*/

49 
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq); 
50  
51 
#endif /* MATHEMATICS_H */ 